can someone tell me about my bass i got for free? (aria)

Someone gave me a bass guitar for free. It is a make called Aria. On the headstock, which is 2 tuners on each side, it says AriaproII. It's got gold hardware. Through body neck. The colour of the bass is like wood (showing lots of grain) but is red with a maple(i think) in the middle. It's got what i think is a humbucker i'd say the middle spot. 3 controls. It also has this written on the headstock:

Specially designed and approved by Aria research development lab. Original custom body Pat 555719.

I was told that in the battery compartment it says it was built in 1981. Has anyone got any ideas about the value of this fretless bass or the history...any infomation at all? I will try get pics as soon as I can. thanks
rowan

Sounds to me a lot like the Aria Pro II SB series from the '80's.
I have a pamphlet on them right here that I've kept for some reason.

The top end of those basses was the SB-1000 (like John Taylor of Duran Duran used to play). These had a single p.u. with a 5 way rotary switch and by-pass switch with an LED indicator. The fingerboard was ebony and it had a brass nut.

The SB-700 had a single p.u. but w/out the rotary switch or by-pass switch. The bodies on both models were Canadian ash w/maple and walnut laminants for the neck. The fingerboard on this one was rosewood.

The SB-R80 series had similar features but with less expensive die-cast hardware and not the brass stuff the other series had.

I owned a SB-900 (TWO MB-II pick-ups) back in the day and I LOVED it! I still wish I had it. I traded it in for a Fretless Fender Jazz Special (I went through a Jaco phase). Oh well...